You can use an IN clause for this. First of all take your array and implode it on , so you get a list of numbers you want to search against. Then provide that list to that IN clause and get your results.

$arr=['1','2','4','5','12','13'];
$values=implode(",",$arr);
$query="SELECT * FROM db_user WHERE supplier_id IN ($values) ORDER BY supplier_id DESC";

Now run that query

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